Trends In Treating Astigmatism

The surgical revolution in treating astigmatism began with the onset of Radial Keratotomy (RK) in the late 1970's and continued into the era of Laser Vision Correction. When a cataract was to be replaced, if you had astigmatism you either had to undergo a procedure like RK called a Limbal Relaxing Incision (LRI) during or after the surgery, or a laser procedure like LASIK or PRK. These all work well.

About 5 years ago there was a new development in Intra-Ocular Lenses (IOL) that not only improved vision after cataract surgery, but also treated astigmatism: Toric IOL's. A study of refractive cataract surgeons like our Dr. White recently reported that 75% now prefer to use these new IOL's rather than LRI's in patients with astigmatism.

"We really like the Alcon Toric IOL when we are aiming to make our  Cleveland patients independent from glasses for their distanc vision needs like driving or watching TV," said Dr. White.  "Our golfers are particularly happy!"

Extra pre-operative measurements like corneal topography are necessary to choose both the power and the orientation of the IOL. Once it's in the eye it is amazingly stable!

The technology of cataract surgery now includes multiple ways to address astigmatism. Dr. White and a majority of the top surgeons in the United States are now opting for a Toric IOL in cases where astigmatism is treated during the surgery.

Astigmatism 101

What is Astigmatism? It's a funny word, isn't it? Lots of people think the word is "stigmatism" and that you have "a stigmatism". That of course means that you could have one or more "stigmatisms", but that's not really how it works!

Astigmatism is an optical term that relates to how an optical system focuses, or doesn't focus, light. In our situation the optical system is the eye! There are three different parts of the eye that make up the focusing elements of our vision system: the TEAR FILM that sits on the very surface of the eye (that's why Dry Eye causes vision problems!), the CORNEA or window to the eye, and the LENS that sits in back of the pupil. Astigmatism is present when the combination of these pieces parts creates two or more focused images from a beam of light.

Most of the time astigmatism is caused by the shape of the CORNEA. In a normal eye, one without astigmatism, the cornea is like the front of a sphere; it's round like a basketball or a soccer ball. A cornea that has astigmatism is longer in one direction than the other. It's STEEPER in one direction and FLATTER in the other. In other words the astigmatic cornea is shaped like a football instead of a basketball.

Whether you are nearsighted or farsighted, if you have astigmatism you will have at least two images focused in the eye. There are lots of ways to correct this, and we'll talk about all of them as time goes on. Be sure to check here, and watch for the videos on the Dr. Whiteboard over on Youtube for more info on ASTIGMATISM.